Conventional vacuum cleaners employ air cooled or air pass through motors for preventing overheating of the vacuum cleaner motor during operation. For operation of small diameter vacuum pressure or positive air pressure driven tools for access to tight spaces, a connection tube assembly or adapter includes a large diameter tube section for attachment to the suction or positive air pressure sides of the vacuum cleaner and a much smaller diameter tube sized to the tool and coupled directly thereto or via a similar sized hose.
Domestic vacuum cleaners sold in the marketplace come in different forms, namely upright, canister, combination canister with upright features of a revolving brush, stick types, hand vacs, shop vacs and battery operated miniature vacs.
Vacuum cleaners, with the exception of the battery operated miniature vacs, use conventional size attachments to either the vacuum side of the (air intake) vacuum cleaner or the positive air pressure discharge side. Generally speaking, the opening or orifice of the hose section coupled to the vacuum intake or air discharge side of the vacuum cleaner has a 11/4 inch inside diameter. Such hose section diameter may vary slightly. The corresponding attachment to these hoses are normally of conventional size and type, for good reason. Air flow is very important. The inside diameter of the attachments permit enough air flow through the attachments to keep the vacuum motor from overheating during operation since most domestic vacuum cleaners use air cooled (or air pass through) motors. Additionally, because the size of the debris being picked up by the vacuum hose can vary to a large degree, a sufficiently large orifice is required to prevent clogging of the attachments. This relatively large size is also needed to deliver enough suction at the point where the attachment picks dust or debris.
Due to the shear size or bulkiness of the attachments, it is impossible for conventional domestic or commercial vacuum cleaners to clean small confined areas such as typewriter keys and the many parts involved in computers and the like.
Miniature (tiny) battery operated vacuum cleaners are currently being sold in the marketplace which have hoses whose diameters are significantly smaller and which claim capability of cleaning such confined areas. However, because of their very size, their usefulness in terms of air flow is significantly limited. Further, because as battery life decreases, so does the air flow, they are normally incapable of providing adequate air flow for an extended period of time. Attempts have been made to meet the need by utilizing tubular attachments having a large diameter section coupled directly to the vacuum cleaner, and a smaller diameter section integral therewith for attachment to the smaller diameter too. Such adapters or coupling attachments are the subject of the following U.S. patents:
______________________________________ Issue U.S. Pat. No. Date Inventor Title ______________________________________ 3,230,269 1/25/66 Nielsen Vacuum Cleaner for Automobiles 4,405,158 9/20/83 Huberman Air Filler Adapter 4,053,962 10/18/77 McDowell Suction-Cleaning Dust Retriever 4,114,230 9/19/78 MacFarland Deflator-Inflator Attachment 4,476,607 10/16/84 Ross Portable Vacuum Cleaning Device 4,479,281 10/30/84 Mikutowski Method and Apparatus for Cleaning Phono- graph Records 4,506,406 3/26/85 LaMonte Attachment Tool for a Vacuum Cleaner Hose 4,688,295 8/25/87 Starnes Vacuum Cleaner Attachment 4,694,529 8/22/87 Choiniere Suction Device ______________________________________
The patents above evidence adapters or extension devices for vacuum cleaners in which the tool bore diameter is considerably less than that of the tube connection to the vacuum cleaner tubular air inlet on the suction side or the positive air pressure discharge on the outlet side of the vacuum cleaner.
Huberman and McDowell lack the provision for air flow other than that through the small diameter axial port on the small tube side of the adapter.
Choiniere employs a large oval opening within the bottom wall of the adapter. Further there is an elongated slot within the adapter tip adjacent to a hole therein. However, the purpose is not to increase the air flow to protect a vac motor but to provide two suction areas within the end and bottom of the blade.
In Nielsen, an elongated slot within the end of a flat flared nozzle provides the primary suction opening for a mini sized vacuum cleaner, in this case attachable to the intake manifold of an automobile engine. The existence of perforations within upper and lower walls permit additional air flow through the adapter but in Nielsen, there is no vacuum cleaner or vacuum cleaner motor needing protection.
Starnes is representative of a tool having a tube diameter corresponding to the hose size of the conventional vacuum cleaner and coupled to the intake. The attachment facilitates cleaning of narrow spaces between furniture pieces and employs narrow elongated brush elements on the end of the tube or alternatively, a further annular cleaning brush with a hollow end bearing the brush bristles and presumably an axial bore.
The prior art known to the applicant teaches adapters for supporting small diameter tools, with the adapters including a larger diameter tubular portion for coupling to a conventional vacuum cleaner hose or directly to the vacuum or positive air pressure ports of a conventional vacuum cleaner.
It is therefore a primary object of the present invention to provide an improved miniature vacuum tool adapter or attachment converter providing dramatic increase in air flow by attachment to a large size domestic or commercial vacuum cleaner which insures prolonged air flow which reduces the possibility of clogging, which insures air flow adequate to prevent overheating of the vacuum cleaner motor and in which the total air flow through the vacuum cleaner may be readily adjusted by varying the size of supplemental openings within the adapter itself.